4B Open Model Matches GPT-5.6 Sol Retrieval at 100x Lower Cost
August 5, 2026
A 4B parameter open-source model post-trained with Castform achieves retrieval accuracy comparable to GPT-5.6 Sol. When paired with Neon's search extensions, the system offers a significant reduction in cost and latency for agentic search workflows.
HOW THIS AFFECTS YOU
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builderYou can replace expensive frontier models with smaller, cheaper open models for retrieval tasks.
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researcherConsider post-training specifically for agentic search decision-making capabilities.